With the advent of IMT-2000, CDMA has emerged at the focal point of
interest in wireless COMMunications. Now it has become impossible to discuss
wireless COMMunications without knowing the CDMA technologies. There are
a number of books readily published on the CDMA technologies, but they are
mostly dealing with the traditional spread-spectrum technologies and the IS-95
based CDMA systems. As a large number of novel and interesting technologies
have been newly developed throughout the IMT-2000 standardization process
in very recent years, new reference books are now demanding that address the
diverse spectrum of the new CDMA technologies.
Short-range COMMunications is one of the most relevant as well as diversified fields of en-
deavour in wireless COMMunications. As such, it has been a subject of intense research and
development worldwide, particularly in the last decade. There is no reason to believe that this
trend will decline. On the contrary, the rapidly crystallizing vision of a hyper-connected world
will certainly strengthen the role of short-range COMMunications in the future. Concepts such
as wireless social networks, Internet of things, car COMMunications, home and office network-
ing, wireless grids and personal COMMunications heavily rely on short-range COMMunications
technology.
In this thesis several asp ects of space-time pro cessing and equalization for wire-
less COMMunications are treated. We discuss several di?erent metho ds of improv-
ing estimates of space-time channels, such as temp oral parametrization, spatial
parametrization, reduced rank channel estimation, b o otstrap channel estimation,
and joint estimation of an FIR channel and an AR noise mo del. In wireless commu-
nication the signal is often sub ject to intersymb ol interference as well as interfer-
ence from other users.
In Helsinki during a visiting lecture, an internationally well-known professor in communica-
tionssaid,‘IntheCOMMunicationssocietywehavemanagedtoconvertourproposalsandideas
to real products, not like in the control engineering society. They have very nice papers and
strong mathematics but most of the real systems still use the old PID controllers!’. As our
background is mainly in control as well as COMMunications engineering, we know that this
thought is not very accurate. We agree that most of the practical controllers are analog and
digital PID controllers, simply because they are very reliable and able to achieve the required
control goals successfully. Most of the controllers can be explained in terms of PID. The
reasons behind this impressive performance of PID will be explained in Chapter 2.
Before I can present design concepts or tactical wireless COMMunications and network
challenges, I feel the need to mention the challenges of writing for a field where some
information is not available for public domain and cannot be included in this book’s context.
Another challenge is the use of military jargon and the extensive number of abbreviations
(and abbreviations of abbreviations!) in the field. Engineering books are naturally dry, and I
have attempted to make it light by presenting the concepts in layman’s terms before diving
into the technical details. I am structuring this book in such a way as to make it useful for
a specialized graduate course in tactical COMMunications and networking, or as a reference
book in the field.
The use of light to send messages is not new. Fires were used for signaling in
biblical times, smoke signals have been used for thousands of years and flashing
lights have been used to communicate between warships at sea since the days of
Lord Nelson.
The idea of using glass fibre to carry an optical COMMunications signal originated
with Alexander Graham Bell. However this idea had to wait some 80 years for
better glasses and low-cost electronics for it to become useful in practical
situations.
This book intends to prepare you to define Unified COMMunications (UC) for
yourself and then get it to work for you.
Each vendor pulls together from its available products a package of features
related to voice, data, messaging, and image COMMunications. That’s UC for
one vendor, but it’s unlikely to match exactly the UC from another vendor.
You need a detailed specification to know what you’ll see installed.
During the past three decades, the world has seen signifi cant changes in the telecom-
munications industry. There has been rapid growth in wireless COMMunications, as
seen by large expansion in mobile systems. Wireless COMMunications have moved
from fi rst-generation (1G) systems primarily focused on voice COMMunications to
third-generation (3G) systems dealing with Internet connectivity and multi-media
applications. The fourth-generation (4G) systems will be designed to connect wire-
less personal area networks (WPANs), wireless local area networks (WLANs) and
wireless wide-area networks (WWANs).
Digital radios have undergone an astonishing evolution in the last century. Born as a set of simple and
power-hungry electrical and electromechanical devices for low data rate transmission of telegraph data
in the Marconi age, they have transformed, thanks to substantial advances in electronic technology,
into a set of small, reliable and sophisticated integrated devices supporting broadband multimedia
COMMunications. This, however, would not have been possible unless significant progress had been
made in recent decades in the field of signal processing algorithms for baseband and passband signals.
In fact, the core of any modern digital radio consists of a set of algorithms running over programmable
electronic hardware. This book stems from the research and teaching activities of its co-authors in
the field of algorithmic techniques for wireless COMMunications. A huge body of technical literature
has accumulated in the last four decades in this area, and an extensive coverage of all its important
aspects in a single textbook is impossible. For this reason, we have selected a few important topics
and, for ease of reading, organized them into two parts.
Mobile radio COMMunications are evolving from pure telephony systems to multimedia
platforms offering a variety of services ranging from simple file transfers and audio and
video streaming, to interactive applications and positioning tasks. Naturally, these services
have different constraints concerning data rate, delay, and reliability (quality-of-service
(QoS)). Hence, future mobile radio systems have to provide a large flexibility and scal-
ability to match these heterogeneous requirements.
